Close coupled electrical motor adapted for flange mounting



Get. 1, 1957 w, B 2,808,525

CLOSE COUPLER ELECTRICAL MOTOR ADAPTED FOR FLANGE MOUNTING Filed Feb.16, 1954 2 Sheets-Sheet 1 INVENTOR F25 Reginald Fi -Beckett BY MMATTORNEY Oct. 1, 1957 R. w. BECKETT 2,808,525

CLOSE COUPLER ELECTRICAL MOTOR ADAPTED FOR FLANGE MOUNTING Filed Feb.16, 1954 2 Sheets-Sheet 2 INVENTOR Reginald T4: Beckett BY M M ATTORNEY2,808,525 Patented Oct. 1, 1957 CLOSE COUPLED ELECTRICAL MOTOR ADAPTEDFOR FLANGE MOUNTING Reginald W. Beckett, Elyria, Ohio ApplicationFebruary 16, 1954, Serial No. 410,664

Claims. (Cl. 310-91) This invention relates to electric motors and isparticularly concerned with fractional horsepower motors used fordriving the fans or blowers and the liquid fuel pumps of pressureatomizing oil burners.

A plate mounted burner is shown in my copending application for PatentSerial No. 152,353, filed March 28, 1950, on Convertible Fluid FuelBurner.

There has been developed for domestic residential heating the so-calledunit heater which comprises a burner of either the liquid fuel or thegas fuel type and a heat exchanger which may be an air heater orfurnace, or a steam or water boiler. In these unit heaters themanufacturer of the furnace or boiler is desirous of providing a compactassembly having a minimum overall dimension to reduce cost, shipping andhandling charges and to occupy a minimum space in use. When either afree standing conversion type of burner or a plate mounted burner of thecharacter referred to is incorporated in a unit heater which includes anenclosing casing it is apparent that any shortening in the overalllength of the burner component is advantageous from several points ofview. Not only does it decrease the overhang in the case of thecantilever burner, with attendant improvement in the vibrationsituation, but with both types of burner it reduces the overall lengthof the unit heater, including the enclosing casing, with attendanteconomies of cost and space.

It is therefore the principal objective of the present invention toreduce the overall length of oil burners. This objective is attained byreduction in the overall length of the drive motor employed in suchburners to actuate the air fan and the fuel pump. It is apparent, ofcourse, that an axially short or close coupled" electric motor hasnumerous uses other than that mentioned and it is therefore a secondaryobjective of the invention to provide a short or close coupled electricmotor for fan application situations where a short motor may be desired.

One of the difficulties encountered in shortening an oil burner motor isthe necessity for providing a rigid support for mounting a fuel pump onthe motor, preferably for direct drive coupling to the motor shaft.Another difiiculty stems from the need or desire to provide within themotor structure a starting switch or relay and a thermostatic safetyswitch or cutout. These and other ditficulties have been largelyovercome in the motor of the present invention by a unique arrangementwhich utilizes a motor end bell to support the fuel pump in direct driverelationship, which provides receptacles for the starting relay andsafety cutout switch and which reduces motor size in general and lengthin particular. As a refinement of the end bell feature the relay andswitch receptacles are accessible from the outside of the motor end bellfor easy repair or replacement of the relay or switch. As a specializedconstruction the starting relay is secured to and supported by a closureor cover for the relay receptacle so that the relay while maintainingelectrically connected in the motor circuit may be physically removedfrom its compartment when the cover of the compartment is removed.Preferably the relay receptacle or compartment has opposite side wallswhich define an access opening continuous across a plurality ofadjoining sides of the receptacle. In this preferred arrangement thecover or closure for the receptacle may conveniently take the form of asheet metal L-shaped stamping. The access opening, continuous across twoadjoining sides of the receptacle, say the top side and the front side,simplifies the removal and replacement of the starting relay by reasonof the ease with which the connecting wires to the relay are manipulatedin the relay changing procedure.

Another objective and motor structural feature of the present inventionis concerned with the front wall or end of the motor which carries ashaft bearing and is remote from the end bell carrying the fuel pump.This front end wall is shaped complementally to the burner housing,preferably with a central protuberance to project into an opening in thehousing Wall. The protruding or projecting central portion of the motorcasing end wall carries the bearing just mentioned so that the bearingextends through or is disposed in the plane of the rear wall of theburner housing on which the motor is mounted, this being a furtherobjective of the invention.

In a refinement of the motor end wall construction just described theshaft bearing is associated with a lubricant chamber or well formed inthe motor front end wall. An oil tube extends between such oil chamberand the top surface of the motor casing, one portion of the oil tubebeing disposed in a recess or radial slot formed in the motor end wall.The construction and arrangement of this lubricating oil chamber andtube is another objective of the invention.

Provision is made for attachment of the motor casing to the burnerhousing by screws or studs each located on a radius wtih respect to theaxis of the motor shaft which radius is only slightly greater than theradius of the motor shell. This advantageous arrangement which reducesthe size of the motor and the radial projection of the attachment earsis accomplished by grooving the outside of the motor casing axially inthe provision of shallow channels which give screw driver access to theattaching screws or studs and facilitate placement and removal of thelatter. As a refinement of this aspect of the invention the motor casingis internally strengthened by axial ribs at or adjacent the location ofthe external grooves, the internal ribs not only providing reinforcementof the casing at the sections having the grooves but also serving tolocate and support the stator frame of the motor.

Other objects and advantages pertain to certain novel features ofconstruction and combinations and arrangements of parts such as theshock and vibration absorbing mounting means, the fuel pump mountingarrangement and the positioning of the open end of the motor casingwithin a centering flange of the end bell, all as will become apparentin the following detailed description of a preferred embodiment of theinvention. This description is made in connection with the accompanyingdrawings forming a part of the specification.

In the drawings:

Figure 1 is a perspective view partly diagrammatic and with parts brokenaway and removed showing the oil burner component of a burner-heaterunit such as described in more detail in my prior patent and applicationidentified above, the burner component incorporating the motor of thepresent invention and the fuel pump being shown in phantom to reveal thesocket in the motor end hell that receives the attaching plug of thefuel pump;

Fig. 2 is a vertical sectional view with parts broken away and removedtaken through the motor of the burner component of Fig. l, the burnerhousing fan and fuel pump being largely broken away and removed;

Fig. 3 is a fragmentary sectional detail taken substantially along line33 of Fig. 2;

Fig. 4 is a fragmentary sectional detail taken substantially along theline 4-4 of Fig. 3;

Fig. is a sectional detail taken substantially along the line 5-5 ofFig. 2;

Fig. 6 is a perspective view of the motor end bell alone to show therelay and safety switch receptacles, this view being taken from thatquarter spaced approximately 90 from the point of view of the Fig. 1perspective; and

Figs. 7, 8 and 9 are top, side and end views of the motor end bell.

The close coupled electric motor of the present invention is ofparticular utility in a burner-heater combination wherein the burnercomponent, comprising housing H, motor M, fuel pump P and electrictransformer 'l, are mounted cantilever fashion on a heater structure S.As in the patent and application referred to the heater struc ture S maybe either a furnace or a boiler. An air tube (not shown) extends intothe heater from the burner housing and may be carried by the heater.Such air tube is arranged to receive the ignitionelectrode and fuelsupply conduit assembly therethrough and to conduct combustion airforced by a fan in the housing H into a combustion chamber within theheater structure S.

The housing H is secured to the heater S by studs 3 which projectoutwardly from the upright heater wall 1 and are received throughsuitable ears or lugs adjacent the front face of the housing. By meansof spacers 2 received on or forming part of the attachment studs 3 thehousing is held away from the heater wall 1, the front face of thehousing being in generally spaced parallel relation to the heater wallin the provision of a passage through which air may be drawn into thefan chamber of the housing through a suitable opening in the front ofthe housing.

The parts of the burner component with which the present invention isconcerned are shown to advantage in Fig. 2, the motor M being invertical section, with the relationship of the pump P, housing H and fan9 indicated by fragments of these parts. The motor comprises a casing 5and a pump supporting end bell 6 which define a chamber containing afield coil assembly 7 and a rotor 8. The rotor is suitably secured on ashaft that turns in bearings, to be more fully described. The airimpeller fan 9 is conventional, being of the sirocco or squirrel cagetype, the numeral 4 indicating a fragment only of the fan hub which issecured on the end of the motor shaft 10 which projects into fan chamber11 of the housing H through an opening 12 in housing rear wall 14.

The bearing for the forward end of the motor shaft 10 comprises a bronzesleeve 15 held as by press fits in aligned bores through inner and outerwalls 16 and 17 of a lubricant chamber 18 which surrounds the bearingsleeve 15. The walls of the lubricant chamber are integral with oneanother and with the forward end wall of the casing. this casing endwall being peripherally joined to annular casing wall 20 that is ofgenerally cylindrical form. The casing 5 may thus constitute an ironcasting in which the generally cylindrical casing wall 20 is integralwith the front end wall and the latter is integral with the oil chamberwalls 16 and 17, in turn integral with one another.

As one of the distinctive features of the present invention, by whichthere is achieved a shortening of the distance between the rear wall 14of the housing and the fuel pump P, the front end wall of the motorcasing 5 is formed to project into the opening 12 in the housing walland, in effect, constitute a closure for such opening. To achieve thisarrangement the motor end wall is formed with an inner annular portion22 which is axially offset in a forward direction from outer annularportion 23. These annular wall portions are integral, there being acircum ferentially extending outwardly directed shoulder 25 at thejuncture. This shoulder is received within the housing wall opening 12in assembly, the interfitting relation serving to locate the parts tofacilitate placement of the at taching screws that hold the motor on thehousing.

The forward offset of the inner annular portion 22 of the front end wallof the motor may locate such wall portion within the fan chamber 11,although, as shown, it is satisfactory if the offset locates such motorend wall portion in the plane of the housing wall, or substantially so.The front wall 17 of the oil chamber structure is, however, offsetforwardly from the plane of the inner annular wall portion 22 and isdisposed wholly within the housing air chamber 11. Thus the plane of thehousing rear wall 14 extends through the lubricant oil chamber 18 of themotor and the bearing or bushing 15 projects through the plane of suchhousing wall.

While for certain applications it is satisfactory to pack the lubricantchamber 18 with grease or oil at the time of assembly, using cottonwadding or the like. indicated at 28, to retain the lubricant in thechamber and to feed the lubricant to the motor shaft 10 through anopening 29 in the lower part of the bearing sleeve 15, it is preferableto provide for supplying lubricating oil to the chamber 18 as through atube 30 which extends radially with respect to the motor axis through afront opening slot 31 adjacent the forward edge of the cylindrical wall20 of the motor casing to an opening 32 in the top portion of an annularwall 33 which joins the inner and outer walls 16 and 17 of the lubricantchamber. To save space inside the motor casing the oil tube 30 isdisposed in radial slot 35 formed in the front wall of the motor casingis continuous through the inner and outer annular wall portions 22 and23 and also through slot 31 to accommodate the offset between the wallportions of the motor casing and to locate the inner end of the oil tube30 in the plane of the inner annular Wall portion 22. Such tube isformed with inner and outer portions offset from one another and joinedby a connecting portion or wow 36. To secure the oil tube in place theinner end may be press fitted in the drill hole 32 through which thetube gains access to the oil chamber 18. A closure assembly 37 may bepress fitted on the outer end of the tube 30, this assembly including aspring biased cap that is manually displaced when it is desired tointroduce oil into the lubricant chamber through the tube.

The Walls 16 and 17 of the bearing and lubricant chamber structure areformed with annular oil trap chambers 38 that surround the shaftoutwardly of the bearing sleeve 15 and are drained into the lower partof the oil chamber 18 through drill holes 39. An access hole is providedin the bottom wall of the lubricant chamber, this hole being tapped toreceive a closure plug 40.

The motor end bell 6 may also comprise an iron casting, this bell havingan end wall portion 42 peripherally joined to an annular generallycylindrical wall portion 43 which is relatively short axially ascompared to the cylindrical wall portion 20 of the casing. The open faceof the end bell is disposed toward the open face of the casing 5, andthe circular meeting edges of these parts are machined to provide atelescopic joint which insures con centricity. This telescopic joint isprovided by an out wardly directed cylindrical surface 44 machined onthe cylindrical wall 20 of the casing 5 about the circular edge of thecasing wall. complemental cylindrical surface 45 is machined on theinside of the edge of the end bell cylindrical wall 43. As a preferredarrangement the edge of the end bell wall is formed with an integraloutwardly offset circular flange 46 in which is machined the annularlocating surface 45. The end face of this flange, indicated at 47, isalso machined to provide a plane locating surface that abuts a radial,circumferentially extending shoulder machined on the annular casing wall20.

To support the motor shaft 10 in the end bell 6 the latter is formedwith a bearing and oil chamber structure similar to that described inconnection with the front end wall of the motor casing. Oil chamber 50which surrounds the shaft is defined by axially spaced walls 51 and 52connected by an annular wall 53. The oil chamber walls are formedintegrally with the radial end wall 42 of the bell, the walls of the oilor lubricating chamber being so arranged that such chamber is locatedwholly within the end bell. The other parts of the oil chamber andbearing structure, being similar to the corresponding parts describedpreviously, are indicated by the same numerals of reference primed.Lubricating oil is introduced into the annular chamber through fitting54 screwed into a tapped hole drilled through a boss cast on the endbell and leading into the lubricant chamber. The fitting 54 includes theusual spring biased closure manually displaced when it is desirable tointroduce oil. The bearing sleeve 15' is of larger diameter than thebearing sleeve 15 to accommodate an end portion 55 on the shaft 10,which is of relatively large diameter. This shaft end portion is formedwith an axial opening that receives pump shaft 56, the intertittedshafts being drivingly connected by means of a conventional couplingstructure, not shown in detail.

The body of the pump P, indicated at 57, is formed with an integralcylindrical boss 58 in which the pump shaft 56 is journalled. The pumpshaft projects out the end of the boss, being concentric to thecylindrical surface of the latter. As a mounting arrangement for supporting the pump on the motor, the end hell 6 is formed with an integralaxially projecting sleeve 60 that receives the pump boss 58. An internalcylindrical face 61 is machined in the sleeve 60 concentric to the axisof the motor shaft 10. The external cylindrical surface of the pump boss58 is machined to provide a smooth sliding fit in the bell sleeve 60.One or more radial set screws threaded through the sleeve 6! andindicated at 62 in the drawings are tightened to bear radially againstthe pump boss 58 and retain the latter in the end bell sleeve, the setscrews resisting both axial withdrawal and relative turning.

The outer circular end face of the end bell sleeve 60 is machined toprovide a plane surface normal to the motor axis. Against this surfaceis abutted a radial shoulder 63 machined on the pump body 57 at the endof the mounting boss 58. The boss 58 is of less axial length than thereceiving socket provided therefor in the sleeve 60 of the motor endbell so that an annular clearance 64 is provided between end face 65 ofthe pump boss 58 and wall 66 at the bottom of the boss receiving socket.Any fuel oil escaping from the body of the pump along the pump shaft 56is released into the annular escape chamber 64 and flows to the bottomof the latter by gravity. A channel 67 formed in the inside surface ofthe pump supporting sleeve 60 and including a vertical portion extendingradially through the end of the sleeve allows escaping oil to run out ofthe end bell socket and escape. This feature is of advantage, in thatcontamination or dilution of the lubricant in the lubricating chamber 50is avoided. Furthermore, the carrying off to the outside of the motorstructure of escaping fuel oil eliminates flooding of the internalchamber of the motor casing and the resultant damage to the electricalwindings and insulation that would be caused by such an occurrence.Within the motor casing the circular metal ring of the iield coilassembly 7 is slidingly received on machined surfaces 69 of single ribs70 and double ribs 7172. These ribs formed integrally on the inside ofthe cylindrical wall 20 of the motor casing are disposed atcircumferentially spaced intervals about the inside of the casing, theindividual ribs being parallel to the motor axis. In machining the ribsto provide the inwardly directed guide surfaces 69 that engage thecylindrical outwardly directed surface of the metal frame of the fieldcoil assembly the machining is carried to the same relative point alongthe length of each rib to provide radial locating shoulders 73 forengagement by the metal frame of the field coil assembly 7. Atcircumferentially spaced points about the Car motor case and adjacentthe cylindrical wall 20 a number of parallel axially extending studs 75are threaded into bosses 76 integrally formed on the inside of the outerannular portion 23 of the front end wall. The studs 75 are receivedthrough suitable openings in the metal frame of the field coil assembly7, the latter being held against the rib shoulders 73 as by nuts 77threaded on the studs 75. The studs 75 also project through openings inthe end Wall 42 of the motor bell and receive nuts 78 that are drawn upagainst the flat bottoms or depressions of recesses 79 molded in theouter surfaces of the motor end bell to hold the latter snugly againstthe radial locating shoulder on the end of the casing 5.

A shock and vibration absorbing mounting arrangement is provided forattachment of the motor and fuel pump unit to the burner housing H, thestructure comprising a plurality of vibration insulating studs 80distributed about the periphery of the front wall of the motor andconnected between radial ears 81 of the motor casing and the housingwall 14. Each vibration absorbing stud comprises a fiat circular disc 82of rubber or the like to the opposite parallel faces of which are bondedas by vulcanization fiat circular metal discs 83 and 84. Projecting inopposite directions from the metal discs and axially aligned with oneanother are threaded studs 85 and 86. Desirably each of these studs isintegral with the metal disc from which it projects, it being feasibleto make the disc-stud element as a brass screw machine product. Thestuds 86 of the vibration elements 8|] are screwed into threaded socketsprovided therefor in the housing wall 14, the latter desirably beingthickened as by an internal boss 87 through which the stud hole istapped. The front face of each of the attaching cars 81 is formed with acircular recess 88 to receive the major portion of the vibration Fabsorbing rubber body 82 of the shock absorbing element 80. The studs 85are received through openings in the ears of and are secured bycylindrical nuts 89 that bear axially against the flat rear faces of theattaching cars 81. The circular sockets 88 are of slightly largerdiameter than the vibration absorbing discs 82 of the mounting elementsto permit slight radial movement of the studs 85 relative to the studs86 in the absorbing of vibration energy. The recesses 88 are eachshallower than corresponding circular bodies of the vibration absorbingmounting elements so that the latter constitute spacers which hold frontfaces 90 of the attaching ears 81 away from the surface of the housingwall 14. In this fashion the front end of the motor is held away fromthe housing, the intervening clearance space provided by the attachingelements receiving an interposed circular fiat ring 91 of felt fiber andserving to insulate the motor from the housing, not only electricallybut mechanically. Since the only physical connection between the motorand the housing is through the circular rubber shock mounting discs 82,the transmission of vibrations from one component to the other isgreatly reduced.

As shown in Fig. 4. the attaching stud 85 is located at a radius fromthe axis of the motor only slightly greater than the radius of thecylindrical wall 20 of the casing. To accommodate the holding nuts 89,the outer surface of the casing wall 20 is formed with axial grooves 92which permit free axial movement of the nuts in placing them on andremoving them from the studs 86. The grooves 92 also provide for screwdriver or wrench access to the nuts 89. On the inside of the cylindricalcasing Wall 20 in the same radial planes as the external grooves 92 thewall 20 is built up or thickened, as indicated at 93, to compensate forthe weakening of the wall sections that would otherwise occur in theformation of the axial external grooves. A further strengthening of thestructure adjacent each of the axial grooves 92 is obtained through therib pairs 7172 which are located one on each side of the radial planepassing through the motor axis and through the center of the externalgroove 92. The forward ends of the rib pairs 7l-72 are each formed intoand integrally joined to one of the internal bosses 76 that receives oneof the axial casing studs 75. In this arrangement the axis of thevibration absorbing mounting element 80, the groove 92 and the casingstud all lie in a common radial plane which also includes the motoraxis.

In the actual motor construction the field coil assembly 7 and relatedwiring and the rotor 8 occupy more space than that indicateddiagrammatically in the drawings, the coils and wires being omitted forclarity to illustrate the construction of the motor casing, bearings andrelated parts with which the present invention is particularlyconcerned. Within the enclosure defined by the cylindrical walls 5 and43 of the casing and end bell, and between the front wall of the casingand the rear wall 6 of the end bell, there is insutficient space toaccommodate the usual motor starting assembly or relay. So that asuitable starting device can be included in the motor component forwiring and testing by the motor manufacturer, the present inventionprovides a receptacle associated with the end bell 6. This receptacle islocated partially inside the profile defined by the end and cylindricalwalls 42 and 43, respectively, of the end bell and partially outsidesuch profile. That portion of the receptacle located within the profileof the end bell walls may. of course, be continuous with the interiorchamber of the motor bell and easing, although it is contemplated toprovide walls integral with the end bell for precisely defining thestarter receptacle if desired. That portion of the starter receptaclelocated outside the profile of the end bell is advanta' geously definedby a pair of spaced parallel side walls 95 and 96 which may be integralwith the end bell walls. These walls may be located at any desiredpoints about the circumference of the end bell, although it is preferredthat they be located at the top so as to provide access to the interiorof the starter receptacle from above. Each wall has a substantiallystraight top or axially extending edge 97 which is substantiallyparallel to the like edge of the other wall and to the motor axis. Theseaxial wall edges are located radially outwardly beyond the profile ofthe end bell and the cylindrical wall of the motor casing. Each wallalso includes a substantially straight radial edge 98 parallel to thecorresponding edge of the other receptacle wall, these vertical straightedges 98 being in a plane normal to the motor axis and spaced axiallyfrom the plane of the end face on the pump receiving sleeve 60. Thuseach of the receptacle side walls 95 and 96 extends up the rear face ofthe end wall 42 of the bell and forwardly across the top of the end bellsubstantially to the circular flange 46 that telescopes over the rearend of the cylindrical casing. The receptacle side walls cooperativelydefine an access opening which is continuous across the top and down therear of the receptacle. This access opening is closed by an L-shapcdcover 100 which comprises a stamping of sheet or plate metal having aflat vertical portion 101 integrally joined to a flat horizontal portion102 along an integral line of connection 103 at the corner of the coverwhere the two fiat portions intersect in a angle. The cover is held inplace as by a screw 104 threaded into an car 165 projecting into the topportion of the receptacle opening from the circular ring flange 46 ofthe end bell. At their lower ends the side walls and 96 are integrallyjoined to the outside of the cylindrical sleeve 60 in which is formedthe socket for mounting the pump. Thus the side walls of the starterreceptacle constitute reinforcements for the end bell and the pumpmounting sleeve. if desired, the lower ends of the receptacle walls maybe thickened. as indicated at 108, these thickened portions beingdrilled and tapped at 109 to receive attaching screws (not shown) forholding the lower part of the vertical cover portion 101 against thevertical edges 98 of the receptacle side walls.

Attached to the inside of the cover as by screws 110 is a starting relay111 which may be of conventional construction, the starter being thusdisposed within the receptacle and supported wholly by the cover 100.Electrical wires 112 connected in the motor circuit in the usual fashionhave terminals not shown) detachably connected to the usual screwcontacts of the starter 111. When it is desired to inspect the starter111 the latter may be readily exposed by removing the cover attachingscrew 104 and withdrawing the starter bodily from the receptacle whileit remains attached to the cover 100 by the screws 110. This removal andinspection of the starter is accomplished without disconnecting any ofthe wires 112 and, in fact, may be done while the motor is in operation,Should it become necessary or desirable to replace the starter 111, thejob can be done without disassembling the motor from the housing or thepump from the motor.

At one side of the pump attaching sleeve 60, preferably opposite thelubricant fitting 54 the end bell is formed with an integral circularboss 114 which projects axially from the rear wall 42 of the bell andprovides a circular receptacle 115 for a conventional thermostaticoverload switch 116. This switch includes a circular metal plate thatoverlies the face of the boss 114 and is attached to the latter byscrews or drive pins. This safety switch is connected to the motorcircuit in the usual manner.

The present invention thus provides a compact structural arrangement foran electrical drive motor to actuate the fan and pump of a pressureatomizing oil burner or the like. The motor casing, comprising anintegral cylindrical wall and a front wall having axially offsetportions, intcrfits with the burner housing on which the motor ismounted and the overall length of the motor is minimized by partiallyremoving the starting relay from the internal chamber of the motor andplacing it in a specialized re ceptaclc at least a portion of which isdisposed outside the profile of the motor end bell on which the pump ismounted. It is apparent, of course, that the fan 9 is selected with anoverall diameter less than that of the circular opening 12 in thehousing wall 14, thereby permitting the fan hub 4 to be secured on themotor shaft 10 prior to mounting of the motor on the housing. Since theannular portion 22 of the front wall of the motor constitutes a closurefor the housing wall opening, it is feasible to fit the fan 9 on themotor shaft with a relatively close running fit between the fan and themotor wall 22. Thus a further space economy is realized over previousconstructions and, in addition, more efiicient operation is obtained.There is less overhang of the fan relative to the motor bearingsupporting the fan end of the shaft and a relatively short motor shaftis feasible.

In accordance with the patent statutes the principles of the presentinvention may be utilized in various ways, numerous modifications andalterations being contemplated, substitution of parts and changes inconstruction being resorted to as desired, it being understood that theembodiment shown in the drawings and described above is given merely forpurposes of explanation and illustration without intending to limit thescope of the claims to the specific details disclosed.

What I claim and desire to secure by Letters Patent of the United Statesis:

1. An electric motor of the flange mounting type particularly adaptedfor use in driving the pump and fan of a fluid fuel burner, said motorcomprising a stator and rotor combination including electromagneticcoils and a shaft, a casing and a bell enclosing the coils, the bellhaving end wall and peripheral rim portions, journals carried by thecasing and the bell supporting the shaft for rotation about a horizontalaxis, a control relay connected in circuit with the coils. the bellbeing formed with a receptacle for the relay, said receptacle comprisinga pair of side walls each generally parallel to the rotational axis ofthe shaft and spaced from one another, one on each side of a verticalplane through such rotational axis, the receptacle walls beingsymmetrically positioned relative to the shaft axis whereby thereceptacle is centered vertically with respect to the shaft axis, and ahollow boss portion on the bell formed with a socket on the shaft axisfor receiving the mounting boss of a fuel pump, the receptacle sidewalls extending onto the boss portion and constituting reinforcing websdisposed in the planes of the spaced parallel side walls, eachreinforcing web being integrally connected to both the boss portion andthe end wall portion of the hell.

2. A short motor for driving the pump and fan of a fluid fuel burner orthe like, said motor comprising a stator and rotor combination includinga shaft for the rotor, coils and a control relay connected in circuitwith the coils, casing means enclosing the stator and rotor andincluding a bell having an end wall, a boss in the end wall and having aportion projecting axially beyond such wall, said boss constituting atits inner end a journal supporting the shaft and at its outer end amount for receiving and supporting a fuel pump to be actuated by themotor, a pair of walls integral with the bell defining a receptacle forthe control relay, said walls extending axially beyond the end wall ofthe bell and being joined integrally to the projecting boss portion, theshaft extending beyond the casing means at the motor end opposite thebell to support and drive a fan received thereon, and journal meanscarried by the casing means for supporting the shaft at a point spacedaxially along the latter from the boss journal.

3. A short motor for driving the pump and fan of a fluid fuel burner orthe like, said motor comprising a stator and rotor combination includinga shaft for the rotor, circular section casing means of less axiallength than diameter enclosing the stator and rotor, said casing meansincluding an end wall and an end bell in spaced relation and an annularwall extending between the bell ad the end wall, hearings in the belland end wall for supporting the shaft, the end wall bearing comprising ahollow boss providing a lubricant chamber, a radial slot in the endwall, and an oil tube disposed in the slot substantially in the plane ofthe end wall and extending from the hollow boss to the annular wall inthe provision of a passage through which lubricant can be supplied tothe chamber, the radial slot having confronting walls closelyparalleling the oil tube to confine and protect the latter againstdisplacement circumferentially of the shaft.

4. A short motor for driving the pump and fan of a fluid fuel humor orthe like, said motor comprising a stator and rotor combination includinga shaft for the rotor, circular section casing means of less axiallength than diameter enclosing the stator and rotor, said casing meansincluding an end wall and an end bell in spaced relation and an annularwall extending between the bell and the end wall, hearings in the belland end wall for supporting the shaft, said end wall comprising innerand outer portions each substantially annular in extent, the inner endwall portion being ollset axially relative to the outer portion of theend wall and connected thereto by an arcuately curved junctureconcentric to the shaft in the provision of a protrusion on the end wallreceivable within a mating opening of a fuel burner to obtain closecoupled characteristics in the motor burner combination, the end wallbearing comprising a hollow boss providing a lubricant chamber, a radialslot in the end wall and continuous across the juncture connecting saidinner and outer portions of the end wall, and an oil tube disposed inthe slot, said tube having an outer portion located substantially in theplane of the outer portion of the end wall and an inner portion offsetfrom the outer tube portion and located substantially in the plane ofthe inner portion of the end wall, the tube extending from the hollowboss to the annular wall in the provision of a passage through whichlubricant can be supplied to the chamber, the radial slot havingconfronting walls closely paralleling the oil tube to confine andprotect the latter against displacement circumferentially of the shaft.

5. An electric motor of the flange-mounting type, said motor comprisinga stator and rotor combination including electromagnetic coils and ashaft, a casing and a bell enclossill ill)

ing the coils, the bell having end wall and peripheral rirri portions,journals carried by the casing and the bell and supporting the shaft, acontrol relay in circuit with the coils, the bell being formed with areceptacle for the relay, said receptacle comprising a pair of spacedgenerally parallel confronting side walls which project outwardly fromthe bell end wall and axially beyond the bell journal and beyond theshaft end supported in such bell journal, the bell also being formedwith a hollow boss projecting outwardly and axially beyond the belljournal and axially beyond the receptacle walls, the interior of saidboss constituting a socket for receiving the mounting boss of a fuelpump, the receptacle side walls extending onto and being integral withthe projecting boss and constituting reinforcing webs integrallyconnected to circumferentially spaced portions of both the boss and theend wall portion of the bell, the receptacle being open between the sidewalls and a closure supported by and extending between the re ceptacleside Walls.

6. An electric motor for driving a rotary fan in a chamber of a housinghaving a wall formed with a shaft receiving opening, said motorcomprising casing means including an end wall for attachment to the wallof the fan housing over the shaft opening, a rotor in the casing meansand including a shaft projecting through the end wall of the casingmeans, bearings carried by the casing means and engaging spaced portionsof the rotor shaft to support the latter for rotation about a fixedaxis, the casing means being shaped complementally to such housing wallfor mounting on the housing with the end wall of the casing meansconstituting a closure for the housing wall opening, said casing endwall comprising an outer portion surrounding the shaft in radiallyspaced relation and receivable against the outside of the housing wallabout the shaft receiving opening in the latter, said casing end wallcomprising an inner portion spaced radially inwardly from said outerwall portion and surrounding the shaft, said inner wall portion beingformed with an internal lubricant chamber, one of said bearings beingmounted within said inner Wall portion, the lubricant chamber beinglocated and connected to supply lubricant to said one hearing, and saidend wall also including a wall portion located between and connectingthe outer and inner wall portions, said connecting portion of the casingwall being ofiset axially from the plane of the outer portion of suchwall to project into the housing wall opening and disposed generally ina plane intersecting the lubricant chamber intermediate the axialextremities of the latter, and the inner portion of the casing end wallprojecting axially beyond the connecting portion of such wall in bothdirections, whereby one end of the inner portion of the casing end wallprojects into the interior of the casing and is surrounded by an annularspace in such casing and the other end of such inner wall portionprojects further into such housing wall opening than the connectingportion of the casing wall.

7. An electric motor for driving a rotary fan in a chamber of a housinghaving a wall formed with a shaft re ceiving opening, said motorcomprising casing means including an end wall for attachment to the wallof the fan housing over the shaft opening, a rotor in the casing meansand including a shaft projecting through the end wall of the casingmeans, bearings carried by the casing means and engaging spaced portionsof the rotor shaft to support the latter for rotation about a fixedaxis, the casing means being shaped complementally to such housing wallfor mounting on the housing with the end wall of the casing meansconstituting a closure for the housing wall opening, said casing endwall comprising an outer portion surrounding the shaft in radiallyspaced relation and receivable against the outside of the housing wallabout the shaft receiving opening in the latter, said casing end wallcomprising an inner portion spaced radially inwardly from said outerwall portion and surrounding the shaft, said inner wall portion beingformed with an internal lubricant chamber, one of said bearings beingmounted Within said inner wall portion, the lubricant chamber beinglocated and connected to supply lubricant to said one bearing, and saidend wall also including a wall portion located between and connectingthe outer and inner wall portions, said connecting portion of the casingwall being ollset axially from the plane of the outer portion of suchwall to project into the housing wall opening and disposed generally ina plane intersecting the lubricant chamber intcrmediate the axialextremities of the latter, the inner portion of the casing end wallprojecting axially beyond the connecting portion of such wall in bothdirections, whereby one end of the inner portion of the casing end wallprojects into the interior of the casing and is surrounded by an annularspace in such casing and the other end of such inner wall portionprojects further into such housing wall opening than the connectingportion of the casing wall, said connecting portion of the casing endwall being formed with a radial slot, a tube disposed in said wall slot,one end of such tube being continuous with the lubricant chamber in theinner portion of the end Wall and the other end of such tube projectingout the casing, and the walls of the wall slot closely paralleling thetube to confine and protect the latter against displacementeircumferentially of the shaft and the location of the tube in the wallslot avoiding interference in the casing space surrounding the innerportion of the end wall.

8. A short motor for driving the pump and fan of a fluid [ucl burner orthe like, said motor comp rising a stator and rotor combinationincluding a shaft for the rotor, casing means enclosing the stator androtor, said casing means including an end wall and an end bell in spacedrelation and an annual wall extending between the bell and the end wall,bearings in the bell and end wall for sup porting the shaft, saidannular wall being formed with integral internal axially extendingeircumferentially spaced ribs inside the casing for locating engagementwith the rotor, the casing means including an integral apcrturcdexternal ear projecting radially outward from the annular wall toreceive a fastener for attaching the motor to a support and including anintegral internal boss projecting radially inward from the annular wallto receive means for holding the stator in fixed relation to the casing,the annular wall being formed with an external axial groove aligned withthe aperture in the ear to provide tool and fastener clearance inalignment with the ear aperture, holding means connected between thestator and the boss. the boss and the car being located in radialrelation to one another on opposite sides of the annular wall, and oneof the internal ribs being located closely adjacent the external grooveand at one end being directly connected to and integral with theinternal boss, said one rib being located within the circumferentialextent of the external ear whereby stresses imposed on the car by such afastenor and on the boss by the stator holding means are distributedaxially along the annular wall by the one rib and such one rib alsoreinforces the annular wall along the length of the groove.

9. A short motor for driving the pump and fan of a fluid fuel burner orthe like, said motor comprising a stator and rotor combination includinga shaft for the rotor, casing means enclosing the stator and rotor, saidcasing means including an end wall and an end bell in spaced relationand an annular wall extending between ill) till

the bell and the end wall, bearings in the bell and end wall forsupporting the shaft, said annular wall being formed with integralinternal axially extending circumferentially spaced ribs inside thecasing for locating engagement with the rotor, the casing meansincluding an integral apertured external ear projecting radially outwardfrom the annular wall to receive a fastener for attaching the motor to asupport and including an integral internal boss projecting radiallyinward from the annular wall to receive means for holding the stator infixed relation to the casing, the annular wall being formed with anexternal axial groove aligned with the aperture in the ear to providetool and fastener clearance in alignment with the ear aperture, holdingmeans connected between the stator and the boss, the boss and the carbeing located in radial relation to one another on opposite sides of theannular wall, and a pair of the internal ribs being located in closelyspaced parallel relation on opposite sides of and in symmetric relationto the external groove, said pair oi. ribs at one end each beingdirectly connected to and integral with the internal boss, said pair ofribs both being located within the circumferential extent of theexternal ear whereby stresses imposed on the car by such a fastener andon the boss by the stator holding means are distributed axially alongthe annular wall by the pair of ribs and the latter also reinforce theannular wall along both sides of the groove.

10. An electric motor comprising an enclosing structure which includes acasing and an end bell, electrical circuit components including a rotorand a stator in the structure, the rotor including a shaft, bearingscarried by the structure and supporting the shaft, an electrical relayconnected in the rotor circuit, the end bell including a pair oroutwardly projecting spaced wall elements generally parallel andsymmetrically disposed relative to an axial plane of the motor anddefining a receptacle for the relay, the end bell being formed with athrough opening spaced radially from the shaft axis, located betweensuch parallel wall elements, and placing the relay receptacle incommunication with the interior of the enclosing structure, said wallelements each being formed with substantially straight edgesintersecting at a corner angle, corresponding edges of the two wallelements being parallel to one another, such corresponding edgesdefining openings into the relay receptacle which intersect one anotherand are continuous across adjacent sides of such receptacle, and aone-piece L-shaped closure mounted across the intersecting receptacleopenings, for facile removal and replacement, said closure havingangularly disposed fiat portions covering said adjacent side openings ofthe receptacle opening.

References Cited in the file of this patent UNITED STATES PATENTS1,175,326 Wilson Mar. 14,1916 1,454,195 Tomlinson May 8, 1923 1,658,858Reis Feb. 14, 1928 1,701,047 Leece Feb. 5, 1929 2,001,799 Seyfried May21, 1935 2,141,971 Desoutter 2- Dec. 27, 1938 2,202,424 Hough May 28,1940 2,465,675 De Lancey Mar. 29, 1949 2,518,815 Polk Aug.15, 19502,607,819 Sutton Aug. 19, 1952 2,656,973 Sutherland Oct. 27, 1953

